Replacement SSD/MBP2012

I know- 6 million of these questions have been asked, but I have (I think) a slightly different approach on mine.

I'm about to order a new SSD on Amazon. Besides the Samsung 850, what other models are good to go with my MBP? I've been running temporarily on a 480 GB spinner since my machine was damaged, so ALL of them will be fast in comparison. (My 7year old Core 2 Quad Q9000 HP lappy has an old SSD in it and I am amazed at how snappy it feels- it's become useful again.) I'm trying to balance capacity, speed, and cost. Which ones can be a simple plug-in replacement for the spinner I have now? Also, if there is anything to note about the different capacities of the mode (such as "the RotBot SSD is great in 512GB but for some reason, the 256 GB drive has an abnormally high failure rate, so avoid that size") I'd appreciate that also. To be clear on my specs- 16GB RAM, 15 inch hi-rez screen (not retina), 2.6 ghz i7.

Crucial are a great brand too and frequently cheaper than the Samsungs.

But honestly any old SSD from a reputable brand would be fine. SanDisk, Crucial, Samsung... I wouldn't personally look beyond those three, though you shouldn't expect much beef with other manufacturers.

You are partially correct. The optical drive has slower response than other types of storage.
And, in the "olde" days, with an EIDE bus used for optical drives, that would definitely stomp on performance on that bus.
But, SATA uses the same protocol for both uses, and doesn't need a slower bus just for use with the optical drive.
Some earlier MBPros had a slower bus for the optical drive, but not since early 2011 models.
Both hard drive slot, and optical drive slot use SATA-3 on your MBPro.

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